Peaceful Uses of Outer Space and International Law
Hans-Joachim Heintze

I. Introduction: Confusion of terms

The term "peaceful uses of outer space" appears in official government statements and multilateral treaties. However, the examination of the state practice leads to the conclusion that this term is still without an authoritative definition. It is a source of considerable confusion and creates a legal grey area.

The widely accepted interpretation of this key term of space law prior to the begin of space age, namely that "peaceful" means "non-military", was soon contradicted by the practice of two space powers. In the period between 1957 and the adoption of the Outer Space Treaty in 1967, these two powers had placed into orbit a number of military payloads and had come increasingly dependent on space technology in their military planning. Since the term "peaceful" continues to be used it is useful to examine the meaning of this ambiguous adjective.

II. History of the term "peaceful"

  1. In relation to outer space

    The term "peaceful" in connection with outer space uses appeared already before the first satellite was launched. US Ambassador Lodge expressed in 1957 the hope, that future developments in outer space would be devoted exclusively to peaceful and scientific purposes. Therefore he proposed that the testing of satellites and missiles be placed under international inspection and participation. A few months later, Secretary of State Dulles, announced the willingness of the United States to establish a system which would insure that outer space missiles would be used exclusively for peaceful and scientific purposes and for the benefit of mankind. In August 1957, Canada, France, the United Kingdom, and the United States called for a study of an inspection system that would assure that the launching of objects through outer space would be exclusively for peaceful and scientific purposes. This proposal was incorporated in UN-General Assembly resolution 1148 (XII). This was a fundamental document, not only because it represented the first General Assembly resolution on outer space but also because it introduced the phrase "exclusively for peaceful purposes" in an UN resolution. President Eisenhower also took part in the debate. He proposed to the USSR, that the two nations agree to use outer space only for peaceful purposes and not for the testing of missiles designed for military purposes. This statement, underlines that the term peaceful, even after the launching of Sputnik I, was being used by the USA as a counterpart to military in the context of outer space activities.

    The topic "Questions of the Peaceful Use of Outer Space" was discussed during the 13th UN General Assembly in 1958. In the debate, nearly all states used the term "peaceful" contrary to "military". Therefore the common understanding was to avoid any military use whatever. The General Assembly adopted after a long discussion the resolution A/1348 (XIII), which recognized as the common aim of peoples that outer space should be used for peaceful purposes only. One important result of this resolution was the establishment of the ad hoc Committee on the Peaceful Uses of Outer Space (COPUOS), which became a regular committee of the General Assembly in 1959. However, neither of these resolutions, nor the comprehensive report of the ad hoc Committee of 1959, attempted to interpret or clarify the term "peaceful".

    While the states, including the space powers, were demanding that outer space be devoted exclusively to "peaceful" purposes, the USA and the USSR were secretly developing satellites that were to serve military objectives. On a highly classified basis the U.S. Air Force contracted the development of reconnaissance satellites already in 1955. From the beginning U.S. space programs have been primarily of a military, not a civilian or scientific nature. Also Soviet space programs over-all have always been driven more by military considerations and requirements than civilian and scientific ones. In 1958 the legal position of the USA with respect to the meaning of the phrase peaceful uses became quite different from the initial rhetoric. The new interpretation meant non-aggressive rather than non-military. Accordingly, all military uses are permitted and lawful as long as they remain non-aggressive. By contrast, the USSR publicly insisted that peaceful meant non-military and that in consequence all military activities in outer space were "non-peaceful" and possibly illegal. In the light of the military uses of space by the USSR this reflected a lot of hypocrisy.

  2. In relation to other fields of human activity

    The use of the term "peaceful" is not limited to outer space documents. After the foundation of the United Nations the term has appeared in several important multilateral agreements, namely, in the Statute of the International Atomic Energy Agency (IAEA), the Antarctic Treaty, the Treaty for the Prohibition of Nuclear Weapons in Latin America, the Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological (Biological) and Toxin Weapons and on their Destruction, the Chemical Weapons Convention and in the UN Convention on the Law of the Sea. Some examples show the connection in which the term peaceful has been used.

    a) The 1956 Statute of IAEA underlines in Article II that the objectives of the agency are to seek to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world and to ensure that assistance provided by it or at its request or under its supervision or control, is not used in such a way to further any military purposes. The article enumerates the functions of the agency. It contains several references to the application of atomic energy for peaceful uses and purposes. In the light of the travaux préparatoires it is obvious, that the drafters of this agreement understood peaceful uses to mean non-military, rather than non-aggressive.

    b) Article I of the 1959 Antarctic Treaty declares that Antarctic shall be used for peaceful purposes only. It explicitly prohibits any measures of a military nature as well as the testing of any type of weapons on the continent. This formula can be understood as the demilitarization of the Antarctic. It is based on the premise that to exclude armaments is easier than to eliminate or control them once they have been introduced. This treaty has often been characterized as the most authoritative interpretation of the term peaceful.

    c) Article 88 of the 1982 Convention on the Law of the Sea, prescribes laconically that the high seas shall be reserved for peaceful purposes. In that context the term peaceful does not mean non-military, because the high seas are navigated by a lot of war ships used for tests of nuclear missiles as well as for military maneuvers. Therefore it is difficult to find the reason for the inclusion of the reference to peaceful purposes.

    III. The term peaceful purposes in multilateral treaties on outer space

    1. In the same time when the negotiations on the Outer Space Treaty took place, the US and the Soviet Union were both committed to using outer space for military purposes, especially for surveillance, communications, navigation and detection of nuclear explosions. The difference between the superpowers was only that the United States in contrast to the USSR made no secret of its military space programs. The Soviet Union continued to treat military activities in outer space in the public with disappointment. By accepting the text of the Outer Space Treaty it implicitly followed the U.S. interpretation of the term peaceful. Contrary to the expectations of many states, the Treaty failed to ban all military uses of outer space. According to Article IV, states shall not place in orbit around the earth any objects carrying nuclear weapons or any other kind of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner.

    2. The treaty gives no definition of weapons of mass destruction, a phrase that is commonly understood to mean, in addition to nuclear weapons, radiological, bacteriological, and chemical weapons, as well as any future weapons possessing large-scale destructive potential. It stipulates that the moon and other celestial bodies shall be used by all States Parties to the Treaty exclusively for peaceful purposes. It explicitly bans the setting up of military bases, installations and fortifications, the testing of any type of weapons and the conduct of military manoeuvres on celestial bodies. It will be noted that the peaceful purposes-clause applies only to the moon and other celestial bodies but not to outer space in general. The wording of Article IV was carefully chosen to ensure that general principle of peaceful uses would not interfere with the testing of weapons such as nuclear ballistic missiles. The adjective peaceful appears also in Article IX concerning the mechanism of settlement of disputes: Any state party to the treaty which has rea-son to believe that an activity or experiment planned by another State Party in outer space would cause potentially harmful interference with activities in the peaceful exploration and use of outer space may request consultation concerning the activity or experiment. It is impressive and shows the understanding of the state parties of the term peaceful that no state has ever requested the consultations provided for by this article. However it could be employed in restraint of certain potentially harmful military activities.

    3. The 1979 Agreement Governing the Activities of States on the Moon and Other Celestial Bodies repeats in Article III much of the Outer Space Treaty. This article prohibits the threat or use of force or any other hostile act on the moon and the use of the moon to commit such an act in relation to the earth or to space objects. This adds in principle nothing to the provisions of the Outer Space Treaty relating to military space activities. Moreover, the fact that 20 years after its adoption it has received only a handful of ratifications, not a single one by any space-launching power, makes it at least for the time being irrelevant to the problem of controlling the military presence in outer space.

    4. A similar reference to "peaceful purposes" in a multilateral treaty can be found in the Space Station Agreement of 1988. According to Article 1 of this Agreement States have to use a manned civil Space Station for peaceful purposes, in accordance with international law.

    5. The 1977 Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques (ENMOD) refers to peaceful purposes in the preamble and in Article III. In both instances it is obvious that peaceful is used in opposition to military. Thus the preamble notes that the use of environmental modification techniques for peaceful purposes could improve the interrelationship of man and nature, whereas military or any other hostile use of such techniques could have effects extremely harmful to human welfare. One important weakness of this treaty is that it does not prohibit all major activities that could negatively affect the earth environment. Non-military ENMOD experiments could be as damaging as those intended for military or hostile purposes. The Convention explicitly stipulates that its provisions should not hinder the uses of environmental modification techniques for peaceful purposes.

    IV. The legal content of "peaceful" under modern space law

    After the adoption of the Outer Space Treaty there were many efforts to elaborate an interpretation of the term peaceful as used in the Treaty. This was due to the continuing and rapid expansion of military space activities of the two superpowers that were also the main authors of the treaty. Whereas the results of the attempts in interpretation remain unfinished to this day, through their conduct before and especially after the conclusion of the treaty, the two leading users of outer space provided the legal meaning to the term peaceful. Under the 1969 Vienna Convention on the Law of Treaties, the words in a treaty must be interpreted in accordance with their ordinary meaning. In general the term peaceful is defined as disposed or inclined to peace; aiming at or making for peace; friendly, amicable, pacific. It is obvious that this description cannot be applied to any current or past military use of space. However, Article 31, of the Vienna Convention provides that in the process of interpretation any subsequent practice in the application of the treaty shall also be taken into account.

    The International Court of Justice declared in the North Sea Continental Shelf Cases concerning the development of customary international law that in addition to widespread practice and representative participation in a convention, the practice must include states whose interests are especially affected. In space law this means that the practice of even one space power, clearly a specially affected state, carried substantial weight in law. That is especially true when this practice is supported by several other states with developing space capabilities. Under consideration of the ambiguity of the term peaceful, as well as the practice of the two state actors in outer space, the conclusion is doubtless that all military uses of space other than those prohibited by treaty were - since the beginning of space exploration and are still today - lawful as long as they do not violate any of the principles and rules of general international law. No state has ever formally protested such an interpretation of the phrase peaceful uses.

    In practice, the military presence in space grew so rapidly that outer space is the most heavily militarized environment, based on the number of military and civilian payloads launched into orbit. Therefore it has been suggested that the term peaceful in the Outer Space Treaty should be reserved only for non-offensive space installations, i.e., for civilian spacecraft and military space hardware other than space weapons. As a de lege ferenda proposal, this suggestion merits attention. However, this is not to say that the legality of some systems in outer space could not be questioned. Nevertheless, because only a widely endorsed multilateral treaty or a declaration by the World Court could designate a particular weapons system or activity in outer space to be unlawful, given the unlikelihood of any such treaty and the traditional reluctances of states to resolve their differences through international adju-dication, the legal characterization of such uses could remain uncertain for a long time.

    In the light of these developments it is not surprising that one has some difficulties with the interpretation of the terms peaceful uses and peaceful purposes. These terms remain the object of contradictory interpretations even though the principal space powers had agreed to treat all military activities in outer space as permitted except those explicitly prohibited by treaty or customary law. Even the term military in the context of space activities and space uses creates problems in interpretation because civilian satellites, such as Landsat, SPOT, can be and are being used for military purposes.

    V. Military uses and international law

    The military of many states have come to rely heavily on outer space technology. This is especially true for surveillance and communications satellites, not merely for the armed forces of these countries but also for monitoring compliance with arms limitation agreements as so-called national technical means of verification. Without satellites, performance of many military missions would become impossible, and performance of others would require large increase in the unit strengths of various U.S. force elements. The great potential of satellites for military functions was discovered soon after the be-gin of space activities and that early discovery explains why military uses of space quickly acquired the status of a lawful activity.

    • Lawful is the use of satellites for communications, navigation, photoreconnaissance, gathering signals intelligence, ocean surveillance to locate and track war-ships, detection of nuclear explosions in the space and earth environments, ballistic missile early warning, and for weather monitoring.
    • States are free to establish space stations, even if serving exclusively military purposes.
    • Aerospace planes can operate in space under only modest legal restrictions. Problems are only due to state sovereignty in air space.
    • Even anti-satellite weapons, except those nuclear-armed and space-based, are not unlawful in general.
    • In general states are free to use measures such as camouflage.
    • Verification is still an important aspect concerning possible future agreement restricting or prohibiting specific weapons systems. By far the most effective and most reliable would be on-site, prelaunch inspection of all objects, both civilian as well as military, destined for outer space. This is the kind of verification not provided for in the Registration Convention of 1975 and which is therefore nearly useless.

    VI. Conclusion

    Even after the end of east-west-confrontation the reaching of agreement on military uses of outer space seems not possible. This is due to the complexity of the problem involved both in preventing the deployment of space weapons and in defining the kinds of military activities that might not be legitimately conducted in space. Therefore the peace-loving nations will need also in future patience, good faith and respect for the concerns of the human race.


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